1. Field of the Invention
The present disclosure relates to a vehicular headlight apparatus.
2. Description of Related Art
There is known a vehicular headlight apparatus configured to control a light distribution pattern of headlights in order that a light illumination area proper for a target object is illuminated by the light emitted from the headlights. For example, refer to Japanese Patent Application Laid-open No. 2006-21631. In such a vehicular headlight apparatus, a light illumination area is determined uniquely by a light distribution pattern. That is, controlling a light distribution pattern means controlling a light illumination area.
When a target object is detected by an object recognition means such as a camera, the above vehicular headlight apparatus changes the present light distribution pattern so that the light emitted from the headlights covers a light illumination area set for the detected target object. For example, when an oncoming vehicle is detected in the high-beam state (the state in which the headlights of the vehicle on which the vehicular headlight apparatus is mounted are in the high-beam state) or the intermediate-beam state (the state in which the headlights are between the high-beam state and the low-beam state), the vehicular headlight apparatus changes the present light distribution pattern so that the present light illumination area excluding an area near the detected vehicle is illuminated. This makes it possible to illuminate to a sufficient distance without dazzling the driver of the oncoming or preceding vehicle.
In the above vehicular headlight apparatus, the light illumination area is changed depending on the position of an oncoming vehicle. That is, the light illumination area is changed so as to follow an oncoming vehicle. Changing of the light illumination area of the headlights is made using swivel motors or the like.
However, the above vehicular headlight apparatus has a problem in that it may occur that the light illumination area cannot be changed quickly enough following change of the position of a target object when the vehicle is running at a high speed on an express way, or when the vehicle is turning sharply. In this case, the light illumination area may deviate from an intended area, causing a problem that the vehicle driver of an oncoming vehicle is dazzled.